The purpose of the identity is to join networks otherwise unavailable to the perpetrator to glean information off of carefully chosen targets. The person may then send a friend request to his/her target in an attempt to fool the person into believing the person is somewhat trustworthy as the friend request comes from a network to which the target belongs.

A parent might sign up for Facebook as a member of his/her son or daughter's High school, with the intent of some of all of the following:
- to send her child's friends "friend requests" to watch their behavior or subtly coax them to talk about her child
- to watch her child's Facebook announcements and wall posts
- to monitor her child's comments on other's facebook pages
- to see pictures and other information

Son in HS: "Who is 'Tara Jordan'? I've never heard of her at school before..
*clicks to accept friend request oblivious to the fauxbook request coming from his mother*
...
Mother of child, posing as fictitious Tara Jordan: "Now I will scour my son's page and his friends' pages to see what he's doing whilst not under my supervision."

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"I was fauxbooked by my mom and she saw all the college photos of me drinking instead of going to class."

"My fauxbook tricks every girl in the sorority to accept my friend request so I can see all of their information."